Priority is claimed with respect to application No. EP 19943319.4 filed in the European Patent Office on Sep. 10, 1999, the disclosure of which is incorporated herein by reference.
The invention relates to an arrangement for reducing the noise level of tobacco-processing production machines acted upon by flowing process air, particularly in the operator region of a production line comprising at least two production machines disposed at an angle to one another.
Production machines of the tobacco-processing industry primarily encompass cigarette-production machines and filter-attachment machines, which are preferably joined diagonally at a 90xc2x0 angle to form a production line. The machines may further include packaging machines and other standard tobacco-industry components, such as filter-production machines and article-transport devices, the latter representing a secondary source of noise. Particularly in the aforementioned production line, an operator, who is preferably positioned in the corner zone between two machines, is exposed to a great deal of machine noise. Previous efforts to reduce the noise have been unsuccessful in preventing operating noises created by mechanical components, and flow noises produced by process air, especially suction noises, from being emitted from the machines and entering the operator region, because it is not possible to hermetically seal the machine.
It is the object of the invention to implement further, more effective anti-noise measures in tobacco-processing production machine.
According to the invention, this object is accomplished in that the process air supplied to the production machines is predominantly conveyed via sound-damping line segments.
In accordance with a preferred modification, such sound-damping line segments are concentrated in a floor region of the production machines.
In accordance with an advantageous modification, the damping measures in the floor region can be particularly effectively supported by the integration of a sound-absorbing floor covering, which is under the production machines, into the sound-damping line segments.
To optimize the anti-noise measures, it is further proposed to provide secondary air-flow gaps as noise dampers between moving or stationary machine or wall sections.
In accordance with advantageous modifications, the flow noises are additionally suppressed by damping mats that form a cladding of the production machines for sound-damping the air-flow gaps.
As a further noise-reduction measure, it is proposed to provide sound-damped air-exit openings on the top of the production machines, so the emitted noise is directed away from the nearby operator region.
The advantage attained with the invention is that, in machines whose noise level is distinguished by a relatively large process-air throughput, such as strand machines and filter-attachment machines having conveying air, including retaining air and control blast air, the flow noises are absorbed, and thus rendered harmless to operating personnel at the locations where the noise is the most intense and has the greatest impact on the operator region, namely in the boundary zone between the surroundings and the machine interior.